induced abortion is perceived as the means to limit family size. Furthermore, many studies from various countries indicate that women who have previously experienced one or more induced abortions have a proclivity to continue this method of birth control.* Even when effective contraceptives become available, this group of vulnerable women may continue to rely on induced abortion as a "tried and true" method of family planning. Another reason may be that the continued use of induced abortion reveals itself as something of a cohort phenomenon. In the early stage of transition, the socially mobile, upper stratum of society adopts small family-size norms more readily and frequently resorts to induced abortion to limit births. With a rise in educational levels and a stabilization of family-size norms, this group turns increasingly to contraception. Yet while the need to resort to abortion decreases for the upper stratum, the abortion wave is maintained, often at an epidemic level, because each of the lower strata cohorts also pass through a stage of abortion-proneness. The upper-middle, lower-middle, upper-lower, and lower-lower strata replace each other progressively as cohorts vulnerable to induced abortion. This process can continue for long periods of time and can be controlled through vigorous contraceptive programs instituted in such a way that the vulnerable strata are reached.' Finally, when abortion becomes widely accessible—as in eastern Europe with the sanction of the law or in Latin America without it—there is generally an inclination to relax contraceptive efforts. THE NEED FOR LIBERALIZING ABORTION LAWS This study of abortion in the demographic transition leads to the conclusion that the liberalization of abortion laws is needed to protect maternal and child health in both transitional and posttransitional countries. A legal environment that not only permits "abortion on demand" in a medically approved setting but also provides a supporting structure for abortion would (1) accelerate the transition in high-fertility countries, (2) maintain or increase fertility decline in low-fertility countries, and (3) attenuate the social discrimination typical of practice under restrictive abortion laws. The question today is not whether women should resort to induced abortion; it is obvious that many do, regardless of the law, the danger, or other factors. The appropriate question asks which policies would best cope with the public health and social aspects of induced abortion. *See (23; 53; 54, Sadvokasova's study). t A similar hypothesis, as applied to Latin America, has been proposed by Requena (40).